The method for conducting a color gradient is a proficient technique that is often employed in the computer-aided graphics. Many computer design software support a palette editor which allows a user to generate their own custom color palette which is used to create some beautiful effects like gradient fill effect. The traditional palette is a one dimensional bar-type color palette, as shown in FIG. 1, built by setting certain control points on it. The user can add/delete/move these control points or change the color of any control points. Colors between every two control points are measured using a linear interpolation function. There exists at least two control points, the head and tail, as shown in FIG. 2. Currently, the user can only set the colors from the head to the tail but not from the tail to the head because these colors are undefined. This limitation will make discontinuity between colors when the colors of the bar-type color palette are to be repetitively used. For example, as shown in FIG. 1, the head is an indigo blue color, the tail is a light blue color and a color gradient is conducted from the indigo blue color to the light blue color. When the bar-type color palette is again used, no color gradient effect between the light blue color (i.e. the tail) and the indigo blue color (i.e. the head) is conducted so that there exists a gap between the indigo blue color and the light blue color, which is indicated by a circle, as shown in FIG. 3.